You said you're running with kernel version 2.6.18-194.26.1.el5, 
whereas the latest SLF 5.4 kernel is 2.6.18-194.32.1.el5.  I'd be 
surprised if updating the kernel helps, but it's something to try until 
somebody else is able to give better advice.

Steven Yellin

On Mon, 10 Jan 2011, Matthew Jones wrote:

> I installed SLF 5.4 on a Dell Precision M4500 and it has generally
> performed well except that it crashes with a kernel panic an average
> about once a day.  I enabled the memory dump on kernel panic and although
> default kernel image doesn't have debugging symbols, I can dump the
> strings in the vmcore file and always find the following:
>
>  ...
> <3>ehci_hcd 0000:00:1d.0: fatal error
> <1>Unable to handle kernel NULL pointer dereference at 0000000000000088 RIP:
> <1> [<ffffffff88000e07>] :ehci_hcd:end_unlink_async+0x2f/0x108
> <4>PGD 1280d1067 PUD 12dc82067 PMD 0
> <0>Oops: 0002 [1] SMP
> <1>last sysfs file: /devices/pci0000:00/0000:00:00.0/irq
> <4>CPU 7
>  ...
> <4>Call Trace:
> <4> <IRQ>  [<ffffffff88000fec>] :ehci_hcd:unlink_async+0x19/0x58
> <4> [<ffffffff8800135c>] :ehci_hcd:qh_completions+0x331/0x344
> <4> [<ffffffff8800181d>] :ehci_hcd:ehci_work+0xad/0x6d1
> <4> [<ffffffff80079374>] end_level_ioapic_vector+0x9/0x16
> <4> [<ffffffff800baff5>] __do_IRQ+0xeb/0x103
> <4> [<ffffffff8800031b>] :ehci_hcd:handshake+0x38/0x49
> <4> [<ffffffff8800463c>] :ehci_hcd:ehci_irq+0x145/0x15d
> <4> [<ffffffff801f7623>] usb_hcd_irq+0x27/0x55
> <4> [<ffffffff80010c3a>] handle_IRQ_event+0x51/0xa6
> <4> [<ffffffff800bafae>] __do_IRQ+0xa4/0x103
> <4> [<ffffffff80012443>] __do_softirq+0x89/0x133
> <4> [<ffffffff8006ca0d>] do_IRQ+0xe7/0xf5
> <4> [<ffffffff8005d615>] ret_from_intr+0x0/0xa
> <4> <EOI>  [<ffffffff80030358>] unix_poll+0x0/0x99
> <4> [<ffffffff800118e9>] do_select+0x261/0x462
> <4> [<ffffffff800118d9>] do_select+0x251/0x462
> <4> [<ffffffff8001ebd8>] __pollwait+0x0/0xe2
>  ...
>
> Are there any kernel updates or command line options that I am missing
> that might fix this?  It also hangs occasionally when starting up when it
> checks for hardware updates, but I can deal with that issue separately.
>
> Here is some system info if it helps:
>
> $ yum list kernel
> kernel.x86_64                     2.6.18-194.26.1.el5     installed
> $ uname -a
> Linux mjones-laptop2 2.6.18-194.26.1.el5 #1 SMP Tue Nov 9 12:46:16 EST 2010 x86_64 x86_64 x86_64 GNU/Linux
> $ /sbin/lsusb
> Bus 001 Device 001: ID 0000:0000
> Bus 001 Device 002: ID 8087:0020
> Bus 002 Device 001: ID 0000:0000
> Bus 002 Device 003: ID 046d:c01a Logitech, Inc. M-BQ85 Optical Wheel Mouse
> Bus 002 Device 005: ID 0a5c:5800 Broadcom Corp. BCM5880 Secure Applications Processor
> Bus 002 Device 004: ID 413c:8187 Dell Computer Corp.
> Bus 002 Device 002: ID 8087:0020
>
> $ demsg
> Linux version 2.6.18-194.26.1.el5 ([log in to unmask]) (gcc version 4.1.2 20080704 (Red Hat 4.1.2-48)) #1 SMP
> Tue Nov 9 12:46:16 EST 2010
> Command line: ro root=/dev/sdb8 crashkernel=64M@16M rhgb quiet
> ..
> SMP: Allowing 8 CPUs, 0 hotplug CPUs
> Built 1 zonelists.  Total pages: 1027656
> Kernel command line: ro root=/dev/sdb8 crashkernel=64M@16M rhgb quiet
> ..
>
> Thanks,
> Matthew.
>
> ------------------------------------------------------------------------
> Matthew Jones                                           Office: PHYS 378
> Department of Physics, Purdue University      Office phone: 765-496-2464
> 525 Northwestern Ave                        Fermilab Phone: 630-840-2859
> West Lafayette, IN 47907-2036          e-mail: [log in to unmask]
>